Combination targeted therapy of VEGFR inhibitor, sorafenib, with an mTOR inhibitor, sirolimus induced a remakable response of rapid progressive Uterine PEComa

Abstract

Perivascular epithelioid cell tumor is a rare tumor. To date, there is no consensus of therapy to be recommended for unresectable disease. For a low incidence and a rarely curable disease, the finding of new therapy is essential. Here we report the first case of a patient with perivascular epithelioid cell tumor whose disease had a rapid progression after surgery and had a rapid remarkable response of combination therapy of a VEGFR inhibitor, sorafenib, with an mTOR inhibitor, sirolimus. This result may have potential to deliver a new treatment option and inhibiting the mTOR pathway combined with inhibiting the VEGF pathways may be a useful strategy for malignant PEComas.

Keywords: Combination therapy; VEGFR inhibitor; mTOR inhibitor; perivascular epithelioid cell tumor; sirolimus; sorafenib.

Figure 1.

Response of sorafenib combined with sirolimus for metastatic PEComa in the lungs (A) CT demonstrated a mass in the right lung before surgery. (B, C) PET-CT showed pulmonary metastases one month after surgery. (D-F) CT showed complete response of pulmonary metastases after combination therapy.

Figure 2.

Pathological and immunohistochemistry features of pulmonary metastasis of uterine PEComa. (A) Tumor cells with prominent nucleoli and irregular mitoses were arranged radially around the blood vessels (white arrow), HE, × 100. Focal fat cells (black arrow) were found within tumor, HE × 100. (B, C) The tumor cells were positive for HMB45 (B), Melan-A (C) by immunohistochemistry staining, IHC × 100.